This application is directed generally to improvements in contact lens disinfecting apparatus and more particularly to a novel and improved plug-in type of contact lens disinfecting apparatus.
Soft and extended-wear types of contact lenses are widely used. These types of contact lenses are made from hydrophilic plastic porous material which can be formed to the desired lens curvature and thereafter will absorb water and become relatively soft and pliable. These types of lenses require frequent cleaning and disinfecting.
Several disinfecting methods have been developed and employed in conjunction with such soft and extended-wear contact lenses. The present invention pertains to a disinfecting unit or apparatus which utilizes a compact and easy to use plug-in type of unit. The unit comprises an electrical heating circuit, a heating element and receptacles for contact lenses. The invention may be utilized either with methods using a saline or other solution within the lens receptacle or methods in which the lenses are sterilized by a dry heat process.
One problem which has arisen with respect to some prior art disinfecting apparatus is that of preventing the user from removing the caps of the lens receiving receptacles while the unit is plugged into the wall socket. Such removal can cause the saline or other solution, in apparatus where said solution is utilized, to be disturbed and possibly contact and corrode other parts of the apparatus. In particular, some of the electrical parts of the unit which may be subject to damage and malfunction in the event of contact with or coating by various solutions.
Another problem is that of assuring the desired full cleaning time, with the contact lenses being retained within the heated receptacles for the proper amount of time necessary for proper cleaning and sterilization. Hence, it is desirable to prevent the user from removing the contact lenses from the apparatus when the unit is plugged in to perform the sterilizing process.
Spillage of cleaning solution may also occur in the event an attempt is made to add solution to the receptacles when the unit is plugged in. Moreover, it has been found that many users employ an extension cord, and will leave the unit plugged into the extension cord at all times. Hence, it is desirable to prevent access to the receptacles and maintain the lids in a closed position when the plug-in type unit is engaged either with a wall outlet or an extension cord, and to effectively require that the unit be removed from the wall outlet or extension cord in order to accomplish both placement and removal of both contact lenses and solution before and after the sterilizing process.
A related problem is that of maintaining the lens receptacles in an upright position during the sterilization process. In general, such plug-in type disinfector units are designed to plug into standard household AC wall outlets. Such outlets are commonly arranged in one of two orientations which are separated by substantially 90.degree. of arc with respect to the required plug alignment for mating with the outlet. It is desirable, however, that the lens receptacles be kept in an upright position with the top openings and their covering caps oriented vertically upwardly, without regard for the relative orientation of the outlet into which the plug-in type disinfector is inserted.